DIY Rotocasting

Rotational molding, also known as rotomolding, is a molding process for creating many kinds of mostly hollow items. The info is not specific to Classic Cylon Centurions, but SURE can be helpful for them and many, many others projects. Here you'll find various threads with great info from our members for the hobby of costuming.
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Re: DIY Rotocasting

Post by Cylon-Knight » Sat Aug 27, 2011 6:39 pm

BUT you still get to wear cool "Mr. Wizard" gloves and lab coat, right? :roll: :twisted:


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Re: DIY Rotocasting

Post by Big Al » Sat Aug 27, 2011 6:48 pm

Cylon-Knight wrote:BUT you still get to wear cool "Mr. Wizard" gloves and lab coat, right? :roll: :twisted:
:evillaugh:
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Re: DIY Rotocasting

Post by groupleaderzeta » Sat Aug 27, 2011 8:20 pm

I found it intresting that he embeded bolts in the back. :blush:
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 2:07 pm

:cylongold: UPDATE: More Resin Calculation Methods


:cylon: Awesome Building Zeta!!!! I asked around on some of the other forums mostly trooper sites, and met alot of good guy's and great builders and got a couple of methods for calculating the resin amount for a hollow casted helmet. ... plus I found 2 more great case mold / matrix mold making tutorials...One of them they had to restore all the pics on the site because the article goes back a few years and links go bad and pic accounts get closed!. :salute:



:cylon: Here are the methods they suggested


:arrow: Method 1

By Stormtrooper Guy

Trial and error

I do mine in multiple coats. I've found that 8oz combined of resin with 4 oz of filler is good for a coat. I typically do 3-4 coats depending on how it works out. I use a filler from Smooth-On called Urefil 3. It's a ground up ceramic powder. It makes them a bit stronger and makes the coats of resin build up better.

--------------------------------------------------------------------------------

:arrow: Method 2

By EVO3

Hey Alan, sorry to reply so late. I also use the trial and error system. However, at this point in the game, there is less error in my estimations. LOL THere are always minor adjustments to be made in volume but not by much. You will want to put enough resin in each coat to just cover the surface of the mold. I do mine a but different than Brian. I use between 6 and 7 coats. It depends on the temp outside. I use Smoothcast 65D for the first 4 layers and Smoothcast 320 for the last 2 or 3 layers. I mix in ATH powder to all my coats with the exception of the first coat. You can get ATH powder at Smoothon as well. The ATH powder expands the resin to help build up the thickness of the helmet. We all have our own ways of doing things. Its just what you find that works best for your style. Hope this helps.

Ive been in the hobby retail business myself, going on for about 18 years now. Its really an advantage to work in a hobby shop when building armor is your real hobby. The strange look i get from regular customers is priceless. Not to mention the little kids that come in asking where all the SW helmets are. LOL

As for helmet thickness, that really varies from helmet to helmet. Although i have about the same volume of reson in every helmet, it doesnt always spread on the helmet evenly. Some areas may have more thickness than others. And from one helmet to the next, one helmet may have more thickness it the bottom, others may havve it on the top. Its just not an exact science. After doing this for the last few years, its like playing an instrument by ear. You just kinda feel it out as you go.

I found my avitar a few years back from some website and it just kinda stuck. I like the disturbing image, and i guess some people relate it to me now, so it follows me wherever i go.

-------------------------------------------------------------------------------

:arrow: Method 3

By Freedo

I guess the formula would be surface area, [including any part of the casting you plan on removing] X the thickness you want. I chose to cast a known volume of wax, then measure the wall thickness of the casting and adjust from there.... I have a 1/2 gal. wax pot that melts wax and maintains a set temp. so that's what I used..... Lacking that I would have found something else, probably a cheap casting resin. Once you know what a certain volume equals in wall thickness, then you can adjust the volume for whatever wall thickness you want, with a fair degree of accuracy................Fredo

-------------------------------------------------------------------------------

:arrow: Method 4 (The Rice Method)

By Jdougn

For what I do trying to calculate surface areas would be nearly impossible. You could just line with the right thickness of clay then pull it all out pound into a cube & calculate. Or, rice & clay would work also. Fill the mold with dry rice & measure the volume. Line the mold with clay the desired thickness. Fill the balance with rice & measure the difference in the volume of the rice. Just an idea.
dn
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 4:52 pm

:cylongold: Case Mold Tutorial Part 1 By CloneSix



Posted: Fri Sep 12, 2008 12:02 am
Post subject: Case molds
Original post located here www.TK560.com (Case Molds)Vacuum Forming, Movie Prop, Sci-fi and GIjOE Forum



:cylon: Case Mold Tutorial By CloneSix

Since Jim was good enough to add this little section, I thought that I would add a few thoughts on the subject.

Case molds, also known as Matrix mold, blanket mold, skin mold, etc. are simple a rubber mold that is supported by a ridged shell. You could simply pour a mold with solid RTV and have a fine mold. At $100/gal for RTV, this makes for a very $$ mold. So if one could have a surface coat of RTV, backed up by a cheaper and more ridged material, it makes for a very economical product.

There are two schools of thought on this topic: 1) rubber first; case second. and 2) case first; rubber second. I am a believer in the second school for the reason that the case material, whether it be plaster or fiberglass, always shrinks more than the RTV. Therefore, it makes sense to create the case first and fill it with the rubber second.

This is done by creating a space for the RTV and building the shell over it. The space is made by protecting the model in a layer of saran wrap to protect it from the clay, and then covering it with a 1/2" of clay. Then the case is built over that. Once the case is done, the clay is removed, leaving a hollow space to be filled with the RTV.

:cylon: This is better visualized with pictures

Start by mounting the model to a good solid surface such as a piece of 3/4" plywood. Don't go cheap here, whatever you mount it to must support the weight of the model, clay, being fiberglassed, or even plaster. In this case, I took some water clay and wrapped it in Saran Wrap. The clay will form a nice cradle to hold the model and the Saran Wrap will protect the model from geting the clay on it.

[attachment=5]clone6_case_mold_01.jpg[/attachment]
In order to get a good parting line from the masonite, I use a square and a pen to mark the outline of the model. Simply go around the model with the square and mark the outer most points of the model.

[attachment=4]clone6_case_mold_02.jpg[/attachment]
When you have made enough points to connect the dots you will have an outline of the model that can be cut out with a saber saw.

[attachment=3]clone6_case_mold_03.jpg[/attachment]
you will notice that the center line is level at 6.5". That is where the parting line will be. I use 1/4" masonite for the parting line, so subtract the 1/4" from the 6.5 and cut some uprights at 6.25"

[attachment=2]clone6_case_mold_04.jpg[/attachment]
Use a little hot glue and glue the uprights to the plywood

[attachment=1]clone6_case_mold_05.jpg[/attachment]
Mount the 1/4" masonite on top of the uprights

[attachment=0]clone6_case_mold_06.jpg[/attachment]
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 5:12 pm

:cylongold: Case Mold Tutorial Part 2 By CloneSix


Now you have a good, solid parting line

Cover the model in Saran Wrap to protect it from the clay.

[attachment=9]clone6_case_mold_07.jpg[/attachment]

Slice up some 1/2" slabs of clay with a clay slicer. A clay slicer is simply a wire stretched between two carriage bolts. The thickness is adjusted by adding or subtracting nuts on the bolts. Two nuts is about 1/2". Add a few washers for thicker slices.

[attachment=8]clone6_case_mold_08.jpg[/attachment]

Here is the model covered with 1/2" of clay + a gasket edge. That is a lip that helps hold the rubber in the shell. The edges slope at 2-3 degrees to lock the rubber in. It also gives the rubber more of a mating surface when the mold is assembled.

[attachment=7]clone6_case_mold_09.jpg[/attachment]

You will notice two things here: the shiny surface is lacquer. The water clay MUST be sealed. Polyester resin that is used with the fiberglass HATES moisture. Give it 5-6 good coats of lacquer. Hell, 10 coats won't kill you. The second thing is the little plastic cup that is sitting upside down on the clay. I put that on the high spot to allow for a pour spout for the silicone RTV, to be added later.

Next, you need a GOOD coat of PVA for release for the fiberglass. I prefer to spray the PVA for an even coat, but it can also be brushed if you don't have a spray gun and air compressor.

[attachment=6]clone6_case_mold_10.jpg[/attachment]

Now you are ready for a fiberglass shell. Get two layers of 1.5 oz mat on and let set.

[attachment=5]clone6_case_mold_11.jpg[/attachment]

Here is a tip: If you wait until the resin gels (gets firm, but not completely hard) you can run a utility knife along the edge and trim a nice clean edge. If you wait until the fiberglass is completely hard, you will need to grind the edge with a belt sander to get a clean edge. GRINDING FIBERGLASS IS MISERABLE- AVOID AT ALL COSTS

[attachment=4]clone6_case_mold_12.jpg[/attachment]

After the first two layers have cured, add additional layers as needed. In this case, I added 3 more layers of 1.5 oz mat to get a 1/8" lay up. 1/8" is strong enough for a mold of this size. Large (heavier molds may require additional thickness.

Once gel-trimmed, and cured, you can flip it over and remove the masonite, and repeat the clay/seal/PVA process for the other side.

Once you have both sides done

[attachment=3]clone6_case_mold_13.jpg[/attachment]

You should end up with everything encased in fiberglass like this.

You are now ready to open up the case and remove clay from one half or the other, it doesn't matter which, but not both. Once open, you have the model sitting in the clay half and you need to use a tool to smooth out your parting line in the clay. Sorry that I don't have a picture for this, but the cleaner your parting line, the smaller the flashing and easier the cleanup.

[attachment=2]clone6_case_mold_14.jpg[/attachment]

Once you have a nice clean edge tooled into the clay, add some keys so the rubber registers back into the same place each time. I use acrylic hemispheres, but you can also poke depressions into the clay with a drill bit. It works the same.

Back to the fiberglass shell - clean out any remaining clay and sand out any rough or gummy spots. (if the water based clay wasn't completely sealed from moisture, some of the fiberglass resin might have not completely cured - not a problem)

Be sure to drill 1/16" holes in all the high spots of the case. this is to let air escape as it fills up with the RTV.


Now you can add the RTV.

NOTE: If you save the clay from the case, you can pound it into a block and measure the dimensions. Why? Because the volume of the clay = the volume of RTV. This is where METRIC rules! Cubic centimeters = grams of RTV (approximately) At $100/gallon, I don't like to waste any.

[attachment=1]clone6_case_mold_15.jpg[/attachment]

Do you see the tall funnel I have? This is because height = pressure. Fill the cone (keep it slender. A fat cone wastes RTV) with RTV and as it fills, it will bleed out the holes that you drilled in the case. Once they bleed out a little, plug the hole with a ball of clay. Add enough RTV so that the entire case fills and the is an inch or two left in the funnel.

NOTE: Be sure to check on the pour every once in a while until cured. If the unthinkable happens, and there is a blow out (or even a small leak) you will come back to the garage in the morning to find a VERY expensive mold of the floor.

Once cured for 24 hrs, remove the second half of the case and clean out the clay. Add a layer of Vaseline to the surface of the RTV and return the case (with the same 1/16" holes drilled for air) and pour the remaining RTV.

This should give you a good case mold that will produce many clean parts.


Here is a Pdf. of This Tutorial

[attachment=0]Case Mold by Clone Six.pdf[/attachment]

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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 9:30 pm

:cylongold: Molding a Vader helmet! Part ONE!


Originaly Posted: Wed Jun 21, 2006 11:16 am
www.proptopia.com (Vader Helmet Part 1)
Post subject: Molding a Vader helmet! Part ONE!
By: venkman71



Hey guys,....

Been a while since I had anything on the bench and with the outcry among our fellow builders that there's too much buying and not enough building going on, I thought it would be a cool thing to walk you through a little tutorial on doing a two part jacket mold with a silicone insert.

It's a little jumpstart to get the creative vibe a-flowin' and some of you may actually want to try this out on your own stuff.

This type of mold is a bit more complex than your normal build-a-box-around-a-buck-and-pour type silicone mold. It takes a lot of time, even more patience, and careful planning.

If it's done right, you'll have a nice, clean, strong mold and the silicone will have a uniform thickness throughout, without any thin spots.

Let's get started shall we.....

And before we start, I wanna apologize in advance because I got the brilliant idea to document the process about four steps into it.

So the best I can do is describe the process up to the first photo.

So,.....off we go!

First up,.....the subject. A meticulously re-sculpted and re-worked Vader helmet, (I think it's an old Don Post Deluxe but don't quote me on that), I've had lying around for years and it was a complete and utter clown-shoe of a piece.

It was warped, cracked, suffered from varying thicknesses throughout the dome and face-mask, the neck line on the mask was a mess, the tusks, grille, eye-wells and chin vent, as well as huge portions of the dome itself all had to be completely resculpted.

It took me months of on and off work, (working when my schedule would allow), and I finally completed the piece. It was ready for rubber!

[attachment=8]Darth 1.jpg[/attachment]

Here's a closeup shot of the face-mask. I re-sculpted the chin vent to reflect the ANH helmet as opposed to the ESB version. The chin vent in the first film was smaller than in Empire. I also sculpted a new mouth grate which is designed to be set back a bit from the edge of the mouth of the mask and will be cast as a seperate piece to be inserted in the final helmet later as an add-on before painting.

The tusk-mounts have been resculpted as well.

[attachment=7]Darth 2.jpg[/attachment]

First up,....I removed the dome from the mask and mounted it seperately on a post and on it's own molding board.

Disregard the clay seam around the bottom of the helmet as that comes later. This photo is the closest version I have to show what the melmet looked like before the clay coat.

[attachment=6]Darth 3.jpg[/attachment]

The helmet "floats" anywhere from 3/4 of an inch to an inch above the surface of the molding board and the shelf that sits under the brow portion of the helmet.

Next up,....

You make a clay rolling board which is composed of a flat piece of wood, (the one I use is about 8X10 give or take), with two "rails" on either side of the board, (about 3/4 in. high), that will act as a depth-gauge.

You then fill the board up with water clay. Packing it down as tight as possible and pushing it as much to the edges as you can. Then you take a piece of PVC tubing, (or anything smooth like a rolling pin of sorts), and roll out an even sheet of clay, cutting off the excess from the edges of the board, leaving you with an even 3/4 in. slab of clay that has a perfect uniform thickness.

Next,...

Cover the helmet with a trash bag, (or any other type of plastic sheeting), so the oil from the clay doesn't damage the sculpture, then cut strips of clay from the rolling board, and begin laying up the clay coat over the sculpture, leaving about a 3/4 in. "lip" around the perimeter of the helmet.

This could take well over an hour, connecting the slabs and filling the gaps until the helmet has a perfect uniformly thick layer of clay around it.

Next,...

I rolled out another board of clay, and cut 1 in. wide strips and ran them down the center of the helmet, (from the top of the dome and radiating out), in a "+" shape, (as it would look if you were staring down at the helmet). I also jam a spray-paint cap into the clay at the top of the dome to act as a pour hole for the silicone.

These will act as "keys" to lock the silicone into the jacket later. I also run another strip around the perimeter of the helmet where the skull portion meets the "samurai flare".

Next,...

I took an acrylic dowel, (about a half-inch) and poked depressions around the "lip" of clay that runs around the perimeter and base of the clay coat. These will act as keys as well that will lock the silicone around the inside edge of the jacket.

Next,....

I roll out more clay and cut two inch wide strips, stand them up on their edges and run them length-wise down the center of the helmet on top of the center "key".

This forms a big clay "fin" that bisects the helmet and clears the way for the first step of the fiberglass jacket.

Next,...

your clay-coat is done, your keys are in, the piece is bisected. Now you are ready for step one of the jacket.

THE BONDO COAT.

Here's what you do. You take a large amount of bondo, (enough that will cover half the clay-coat with some to spare), and fiberglass resin.

You combine the fiberglass resin and the bondo in a medium sized bucket and mix it until it's a paste of medium to thick consistency.

Then you add the Bondo creme hardener, and the fiberglass catalyst, (kicker) into the mix, (follow the directions) and mix everything until it's blended into a tan-colored thick paste.

Next up,..

Vaseline the molding board around the base of the sculpture and slather the bondo coat over the first half of the clay-coat, over the lip and onto the board itself.

When the bondo reaches the consistency of soft leather, trim the excess so it's got a neat edge, and let it dry the rest of the way.

Once the bondo coat is dry, you need to apply "fiberglass MUD", (a mixture of Cabosil or "resin-thick" with fiberglass resin into a jelly-like mixture).

Apply the "MUD", (after kicking in a few drops of fiberglass catalyst), onto the bondo, rounding out the corners and undercuts so the fiberglass doesn't have trouble sticking up into sharp corners, (around the keys etc.).

Next,...

Fiberglass the first half of the jacket, applying the glass-weave in palm sized patches and covering everywhere you did the bondo-coat.

Next,....

Once the first half of the fiberglass jacket is dry, remove the "clay-fin", apply vaseline to the inside edges of the first half of the jacket, (if you don't, the second half of the jacket will bond to the first half and you're screwed), and repeat the bondo-coat, mud and fiberglass jacket to form the second half of the jacket.

The jacket is done, and this is what you have, (now the pictures start)

[attachment=5]Darth 4.jpg[/attachment]

Then, trim the excess fiberglass, as much as possible while it's still connected to the board), from the edges of the jacket, drill screw holes down the entire length of the fin and seperate the two halves of the jacket from the dome. This takes some work but once it's done, this is what you have.

[attachment=4]Darth 5.jpg[/attachment]

Next,...

Clean the clay out of the halves of the jacket. This will take some time, the drier the clay gets, it will chip out. Once most of it is out, clean the inside of the jacket with rubbing alcohol.

This is what you get,...

[attachment=3]Darth 6.jpg[/attachment]

Here's a good shot that shows you the space between the helmet and the jacket.

[attachment=2]Darth 7.jpg[/attachment]

Next,...

Build a clay wall inside the helmet that will block off the space between the helmet edges and the molding board and the brow mount.

The brow mount has a space so I can reach in and make sure the clay wall is reinforced from the inside of the helmet. It needs to be strong so the silicone does not break the seal and leak out.

[attachment=1]Darth 8.jpg[/attachment]

Next,....

Apply a coat of vaseline to the inside of the two halves of the jacket, (to make the silicone easier to de-mold once it's done), clamshell the two halves to eachother, bolt them back together over the helmet dome and secure the jacket down to the molding board. I bolt it down and then hot-glue the edges, as well as the fin up the center. Make sure you take time and do it right. If there is even a pin-hole, the silicone will find it and leak out. It's relentless.

[attachment=0]Darth 9.jpg[/attachment]

Before securing it down, I drill air-holes along the bottom lip of the jacket as well as adding extra keys in the surface of the jacket itself by drilling 3/4 in. holes in various places.

The extra holes have a dual purpose. They act as extra keys, and more importantly, help you make sure that the major parts of the melmet are not touching the inside of the jacket anywhere.

This step is not mandatory and you can absolutely get away with not doing it. However, if you do, make sure to secure the holes with either thick clay, or hot glued disks.

The last thing you want is a silicone leak from any of these holes. I use a killer indistrial strength tape, (not for everyone) that works well but it's probably not the best idea.

It's worked fine so far but I'm most likely bucking the odds.

Bottom line,....plug up the holes good and strong.


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Last edited by Big Al on Mon Aug 29, 2011 10:45 pm, edited 1 time in total.
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 9:36 pm

:cylongold: Molding a Vader helmet! Part ONE! Cont.

Next,....

Pour your silicone. For this, it took about two gallons. You will need to watch the air-holes on the base and as the silicone starts to seep out, plug the hole with clay. Keep a glue-gun on hand and extra clay in case of leaks. The first two hours are crucial for this and you have to keep an eye on the mold. Once the silicone starts to kick, the risk is less.

It's a lot harder for silicone to leak as it thickens up but for the first few hours,...don't plan on going anywhere.

[attachment=1]Darth 10.jpg[/attachment]

After about 6-12 hours, depending on humidity and heat, the silicone will be dry. Un-bolt the two halves of the jacket, un-screw it from the board, chisel the hot-glue seam off and work the two halves of the jacket apart.

Then peel the silicone sleeve off of the helmet, clean it with alcohol, trim the flashing and fit it back into the jacket.

[attachment=0]Darth 11.jpg[/attachment]

Your mold is done!

Next up,.....casting a dome from your new mold!!!!!

But that's later!

Hope you enjoy!

V71
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 9:55 pm

:cylongold: Molding a Vader helmet! PART TWO!!!


Well,...

On last week's episode entitled: Molding a Vader Helmet; Part one!
We saw spine tingling action as the mold was finished!

When we were done, it looked something like this,.....

[attachment=4]Darth 1.jpg[/attachment]

If you think of creating the mold as say,......dinner, then the next part is most definately dessert!

Next up,.....

Casting a helmet dome

First, I clean out the silicone insert with alcohol, let it dry, (which doesn't take long, as alcohol evaporates quickly), and coat the inside of the silicone insert with a light dusting of baby powder, brushing it over every nook and cranny.

This helps prevent air bubbles.

Now you're ready!

And since you don't wanna just fiberglass right into the mold, you need a step one!

You need something to help capture the surface detail and in this case, it's a two part brushable resin called 1630.

It comes in a "gallon kit" which means a gallon of the "A" compound and a gallon of the "B" compound. One is milky white in color and the other is black.

They mix in equal parts, either by weight or by volume, and in whatever quantity you feel you may need to coat the inside of the mold.

You'll need an electric mixer, ie: a drill, (with a cord, NOT battery operated), and a mixing head.

You cannot mix 1630 by hand. You'll be there till your grandchildren are in college, trust me.

So,....mix up the 1630, (50/50 ratio), and dump it into the mold! Now you take a chip brush, (30 cent cheapie one from Home Depot, OSH, or Lowes), and brush the resin up the sides and into the undercut of the brow ridge.

Coat every inch of the mold as completely as you can and then let it set.

This takes about 20 minutes, give or take.

What you get is this,....

[attachment=3]Darth 2.jpg[/attachment]

Next up,....

Fiberglass Mud!

Yep! More mud. Which, as you should know by now is a mixture of Cabosil, (Resin thick), and fiberglass resin that forms a jelly-like mixture.

Mud is very important in filling areas that the fiberglass weave will have trouble getting itno,...in this case, the undercut along the edge of the helmet and especially the brow section, which is a very deep undercut.

So,.....mix in a few drops of fiberglass resin into a cup of mud and then brush the stuff into the corners, into the lip of the helmet and the brow. Once that's done, start glassing!

Do NOT wait for the mud to dry!

Just start right away. You pick up a piece of fiberglass weave, give it a coat of resin, slap it into the mold, soak it with more resin and tamp it down.

Continue this, overlapping the patches until you've covered every bit of area inside the mold!

The result,....

[attachment=2]Darth 3.jpg[/attachment]

Now drying time may vary depending on heat and humidity, so basically just keep an eye on it. If it's tacky, leave it. If it's dry as a bone to the touch, you're good.

Now,...this goes without saying but you need to do this in a well ventilated area. Fiberglass is heavy on fumes and toxic. Use a good respirator and latex gloves. Keep acetone on hand for cleanup and for soaking your brushes after every step.

Next up,....

Pulling the piece!

Seperate the two halves of the jacket, work your fingers up under the lip of the silicone insert and gently roll the mold up, working it gently and patiently as it peels away from the newly cast helmet underneath.

Take your time with it. The things not going anywhere.

Once the insert is off, drop it back into the jacket and take a look at your newly cast Vader helmet dome!

[attachment=1]Darth 4.jpg[/attachment]

Next,....

Trimming the excess!

Just what the title implies! Don some gloves, a respirator and get out your Dremel with it's sanding wheel!

Do it outside, there will be a LOT of fiberglass dust. You do not want to breathe this stuff in! Bad! Bad!! Bad!!!

Take your time, pay attention to your edges and craft that baby into shape.

You should have something that resembles this!

[attachment=0]Darth 5.jpg[/attachment]

Now that THAT'S out of the way,....

On to the facemask!

Well,....as soon as I can get to it, that is,......

MORE TO COME!

Sean
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 10:09 pm

:cylongold: MOLDING A VADER HELMET PART 3! The facemask!!!


Well,...

Now that we got the Samurai dome out of the way, it's onto the easier, (well, relatively), part.

THE FACEMASK!

Thankfully, I started documenting this one from the beginning, so I can

show you what I had to tediously explain in the first part of the helmet molding post.

First up,......

Sealing it up!

You gots' ta plug up the eye-wells, mouth and chin grate, as well as the top of the connecting ring,which is hollow PVC.

[attachment=4]Darth 1.jpg[/attachment]

In this case I did it with foamcore.

BTW,....before I get a billion e-mails and observations about the mask being a little warped and lopsided,...I KNOW.

So was the original. It was hand sculpted in record time so whatever flaws the originals may have had, so did this one and unless I wanted to resculpt the whole thing from scratch, (which I didn't), I fixed all that I could short of redoing it, and the dome will hide the rest. When it's together and especially when it's painted, you don't notice AT ALL.

Here's a reverse angle!

[attachment=3]Darth 2.jpg[/attachment]

next,.....

Building the mounting wall!

Now I have to build a wall that the helmet will sit on. I do this with foamcore as well as well as cutting a flange for the neck mount

[attachment=2]Darth 3.jpg[/attachment]

Next up,...

Starting the clay coat!!!

I secure the helmet onto the molding board, glue the foamcore wall securely down to the board from the inside of the mask, then claying up the seam and finally gluing the foamcore neck-mount into place.

Then I cover the mask with plastic, (in this case, a kitchen trashbag), roll out the slabs of clay on the rolling board, cut it into strips, and begin the clay coat

[attachment=1]Darth 4.jpg[/attachment]

After some quality shaping time,.....the clay-coat is done!

Well,...almost...

[attachment=0]Darth 5.jpg[/attachment]

Now it needs to be smoothed out, the keys have to be put onto it and the fin needs to be added!

But !,....

I,......haven't,......done it yet....

MORE TO COME!!!!!!!!!!

Stay tuned, lads!

Later!

V71
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 10:28 pm

:cylongold: Molding a Vader Helmet, PART FOUR! 7-2-06!


Well,...

Spent some time in the shop today,....had to go in late in the afternoon as it was just shy of 100 degrees here today,.....just about 90 in the shop so you gotta pick your time, y'know?

Whe we last left the Facemask it had a complete clay coat on it.

Like so,....

[attachment=9]Darth 1.jpg[/attachment]

So here is the next step,.....putting the keys in! Take a gander!

[attachment=8]Darth 2.jpg[/attachment]

The keys will, of course, help it sit tight and correctly into the jacket with no slipping around. Assuring a clean and unwarped casting every time.

Next up,...putting the fin on to bisect the jacket. Here it is!

[attachment=7]Darth 3.jpg[/attachment]

Next up,....

The bondo coat,as referenced in the Molding a Vader Helmet Part one thread. This is what it looks like.

[attachment=6]Darth 4.jpg[/attachment]

Once it's almost dry, (the consistency of soft leather), I trim the bottom edge for so it's nice and clean.

[attachment=5]Darth 5.jpg[/attachment]

Now comes the mud coat,....also as referenced in Part one

[attachment=4]Darth 6.jpg[/attachment]

Now we come to the fiberglass jacket....both sides!

[attachment=3]Darth 7.jpg[/attachment]

Now,...once the fiberglass is dry, you drill bolt holes along the length of the fin and seperate the two halves of the jacket.

Clean out the clay, wipe down the inside of the jacket with alcohol, then drill your air and spy holes.

[attachment=2]Darth 8.jpg[/attachment]

Fit the mold back over the facemask, bolt it down to the molding board, bolt the jacket back together, and seal the seams, (around the base, collar and up the fin), with hot glue.

[attachment=1]Darth 9.jpg[/attachment]

seal the holes with heavy duty adhesive tape,....

[attachment=0]Darth 10.jpg[/attachment]
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 10:31 pm

:cylongold: Molding a Vader Helmet, PART FOUR! 7-2-06! Cont.


Pour the silicone! Watch for leaks for the first few hours!

[attachment=0]Darth 11.jpg[/attachment]

The mold is drying in the shop right now, so more to come tomorrow!

Later!

V71
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Re: DIY Rotocasting

Post by Big Al » Mon Aug 29, 2011 10:38 pm

:cylongold: Molding a Vader Helmet! FINAL INSTALLMENT!


Well,....

Finally,....You folks that have witnessed this journey from the beginning now get to see the culmination of all of this crazy felgercarb!

When last we left,.....the silicone had been poured and the mold was curing!

Observe! For memory refreshment purposes!

[attachment=4]Darth 1.jpg[/attachment]

Today, (well, technically, midnight last night, cause I couldn't wait), I went to the shop and pulled the mold!

[attachment=3]Darth 2.jpg[/attachment]

Man! That foamcore collar is just about done!

Now,....if ya wanna see how I did the fiberglass casting, refer to part one of the Vader Helmet tutorial, but for those that know what I did,....here's the results!

[attachment=2]Darth 3.jpg[/attachment]

A nice, clean cast, and as you can see,....I've started drilling out the eyes and mouth! .

FYI,...the top portion is PVC tubing, ( I think it's 3 in.), slipped into the mold and molded directly into the facemask itself.

After this,...I take the coupling ring that fits this pipe, (also PVC and in the same section that you'd find the smaller PVC), and test fit it over the facemask, hit the edge of it with hot glue, and set it into the dome for a fitting.

Once it's set a bit, I slip the facemask out of the coupling and secure the remainder of it in there with hot glue for the time being until I can do another resin coat for the inside of the dome and seal it in there.

I cast up the mouth grate in resin, and voila,.....

[attachment=1]Darth 4.jpg[/attachment]

A finished rough casting of a David Prowse-sized Darth Vader helmet, ready for finishing and painting!

And that is how you do it!

Hope you guys enjoy!

Later!

Sean


Here is a Pdf of this tutorial
[attachment=0]Darth Matrix Mold Tutorial.pdf[/attachment]

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